1. Technical Field
The present invention relates to a circuit module including at least one semiconductor chip that is mounted on a wiring substrate and molded with a molding material, and a method for manufacturing such a circuit module.
2. Related Art
With a miniaturized circuit module, a semiconductor chip (bare chip) that is not encapsulated in a package is mounted on a wiring substrate by wire bonding or flip chip bonding, and then the semiconductor chip on the wiring substrate is molded with a molding material in order to protect the semiconductor chip and the like.
For example, a plurality of semiconductor chips are mounted on a mother board in which a plurality of wiring substrates are continuously arranged, the semiconductor chips are molded with a molding material, and thereafter the mother board is cut by punching with a die (die cutting). The plurality of wiring substrates are thereby separated. At this time, if the wiring substrates have a small width, the molding material spreads over the widthwise sides of the wiring substrates, and thus the molding material is undesirably cut by the die during punching.
However, the molding material is brittle, and thus if cracking occurs in the cut surfaces of the molding material, a molding defect occurs, resulting in a low manufacturing yield of the circuit modules. There is another problem in that if, for example, a residue of the molding material adheres to the end faces of the wiring substrates, an additional step of removing the residue of the molding material is necessary.
In particular, according to a transfer molding method, a plurality of semiconductor chips mounted on a plurality of wiring substrates are collectively and continuously molded with a molding material, and thus when the molding material and the mother board are cut by punching using a die, cracking is likely to occur in the molding material. Also, even when the molding material and the mother board are cut by using a scribing method, cracking is likely to occur in the molding material. For these reasons, it has been difficult to remove the molding material along the end faces of the wiring substrates.
As a related technique, JP-A-2013-105992 (paragraphs 0006, 0048 and 0065, and FIG. 12) discloses a method for manufacturing a substrate module with a built-in semiconductor device, with which it is possible to achieve high integration and miniaturization of semiconductor devices having a specific function, as well as achieving simplification and improved efficiency of the manufacturing steps relating to mounting components. According to this manufacturing method, a plurality of substrate modules with a built-in semiconductor device are obtained by cutting a core substrate, in which a plurality of core substrate regions (substrate module forming regions) applied to a substrate device portion are continuously provided, along dicing streets into substrate module forming regions so as to singulate the substrate modules.
According to JP-A-2013-105992, a plurality of substrate modules can be obtained by cutting the core substrate, in which a plurality of substrate module forming regions are provided, along the dicing streets. However, JP-A-2013-105992 contains no disclosure of cutting a core substrate on which a plurality of semiconductor devices molded with a molding material are mounted. Also, if the core substrate is cut from one end to the other by dicing, a large amount of residue of the core substrate or insulating layer is generated, and the problem of contamination occurs.